The present invention relates to slide mounting work stations and apparatuses having a substantially enclosed work space and an access opening thereto.
In the performance of microscopic evaluation and diagnosis of human and animal fluids and tissues, fluid and tissue samples or specimens are treated with a variety of reagents prior to mounting or cover slipping of the samples on glass slides or the like. Many of the chemicals or reagents utilized, such as xylene, are volatile and toxic and have associated with them noxious and possibly carcinogenic fumes and odors. It is, therefore, necessary to protect the health of technicians or workers who perform the slide mounting operations from the harmful effects of these fumes.
A common response to the problem has been the installation of a ceiling mounted fume hood over the working area for the purpose of drawing fumes upwardly into the hood and out of the laboratory. A major drawback of conventional fume hoods, however, is that the air flow direction is vertically upward from the work surface so that the unit tends to pull the toxic fumes past the technician's face, resulting in the inspiration of fumes of the possibly carcinogenic reagents prior to exhaustion of the same out of the laboratory. In addition, the unit must draw room air through it at an excessively high flow rate in order to effectively reduce the concentration of toxic fumes in the work area. The use of such high air flow rates is extremely inefficient from an energy conservation standpoint since the heated or air conditioned room air must be constantly replenished to compensate for that exhausted with the fumes through the fume hood. Furthermore, even with the high air flow rates utilized by these units, significant concentrations of toxic fumes remain in the working environment because the fumes of a number of the reagents utilized are heavier than air and, therefore, tend to fall rather than to rise into the fume hood.
In response to these drawbacks, various work stations have been developed with the object of permitting the operator to insert his hands or instruments through an access opening into the interior of a defined work space while at the same time substantially preventing contamination of the ambient atmosphere by fumes within the enclosed work space. However, prior art units presently known circulate air in and through the device with the result that disturbing or eddy currents often form within the enclosure and at the entrance to it. To minimize the development of eddy currents, a relatively high air flow rate is utilized. The movement of air at such high rates is extremely disrupting in the performance of slide mounting procedures and results in a rapid drying of the tissue samples and of the reagents utilized to maintain the same in a moist condition. This high rate of air flow must be avoided because once the tissues dry, they become opaque and, therefore, unusable for microscopic evaluation.
As a consequence, the present invention seeks to provide a substantially enclosed work space or area and an access opening thereto such that a user may perform slide mounting procedures therein without contaminating the user or the ambient atmosphere about the apparatus with toxic fumes present or generated within the work space.
It is another object of the present invention to provide a slide mounting work station wherein only limited portions of the user's body are permitted to enter into the work space while the remainder of the user's body is isolated and protected from toxic fumes within the interior of the work station.
It is a further object of the present invention to provide a slide mounting work station wherein the withdrawal of toxic fumes from the enclosed work space is performed without causing the development of disturbing eddy currents therein.
It is still another object of the present invention to provide for the withdrawal of toxic fumes from the work space while bathing the portions of the user's body inserted into the work space in clean room air so as to prevent such inserted body portions from being attacked by the toxic fumes without producing disturbing eddy currents.